The design of KDE software, and by extension the KDE HIG, is made with
convergence in mind. Convergence means that a piece of software’s user
interface can immediately adapt its user experience to the particularities of
each type of device that it can run on (desktop, laptop, tablet, phone, etc).

For information regarding the differences between a user interface and the user experience, see the Glossary.

The KDE HIG defines an optimal user experience for each device type, as
described in device type.

Convergence requires an understanding of the commonalities in the user
interface. Convergence can then be implemented by providing variations of
the common UI components which correspond with the optimal
user experience for each device’s usage model.

The best way to create convergent applications is to follow the recommendations
and best practices from the KDE HIG, and build your app using the Kirigami UI
toolkit, which provides many of these patterns and components “out of the box”
so that they can be easily integrated.